Typically the primer slide has little to no stress on it. So it's rare for it to break.

When I added the PrimerCop to my press, the first version of the lower mount had a section that rubbed against the wheel on the primer slide as it went by to its lowest position during seating. (The current version of that mount does not contact the wheel at all.)

It worked fine like that, but a friend of mine was seating his second primer, and was a little too aggressive with the handle as he pressed it forward. The wheel caught the lower IR break-beam mount instead of rubbing. The result was a broken slide.

The replacement was about $35.00 with shipping, so I decided I needed to see if I could make one myself.

This part is printed at a 0.10mm layer height with 100% infill using PLA. It works perfectly.

I was able to salvage and use the shaft and wheel from the broken slide.

The 3D printed holes were all very close, and a drill bit finished them out perfectly.

I used a 1/4" endmill in my drill press at 300 rpm to mill out the groove in the top. Without that groove, the bottom edge of the next primer up will grab the slide and prevent it from returning.